Classification of Wine Quality with Imbalanced Data

We propose a data analysis approach to classify wine into different quality categories. A data set of white wines of 4898 observations obtained from the Minho region in Portugal was used in our analysis. As the occurrence of events in the data set was imbalanced with about 93% of the observations are from one category, we applied the Synthetic Minority Over-Sampling Technique (SMOTE) to over sample the minority class. The balanced data was used to model a classifier that categorizes a wine into three categories as high quality, normal quality, and poor quality. Three different classification techniques were used: decision tree, adaptive boosting (AdaBoost), and random forest. Our experiments show that the random forest technique seems to produce the desired results with the least percentage of error.